Since there are so many good answers here, I want to ask a quick question.

I've pretty much conquered my ladder problem, as long as I start the needle with a knit stitch, so I always rearrange so that I can do that if possible. But now, I am trying a pattern that alternates several purl rounds with several knit rounds (so that it kindof rolls up, do you know what I mean? Like the beehive hat in Stitch N Bitch Nation), and I ALWAYS get longer stitches between the needles on the purl rounds. One pattern I tried had you turning your work inside out for the purl rounds, so that you could knit them, but I didn't like the hole it left when you switched directions.

No matter how tight I pull it on those first two stitches, I always get ladders on purl rounds. I need a magic trick !